1、 ENGINEERING MATERIAL SPECIFICATION Date Action Revisions Rev 02 2015 09 21 N Status Replaced by WSS-M7C90-B1 M. Katz, NA 2004 03 11 Revised Para 3.0 inserted; paras 3.1, 3.2, 3.3, 3.9 and 4 deleted 1995 08 16 Activated J. A. Faunt Copyright 2015, Ford Global Technologies, LLC Page 1 of 3 RUST PREVE
2、NTIVE, WATER BORNE WSB-M7C90-A NOT TO BE USED FOR NEW DESIGN 1. SCOPE The material defined by this specification is an alkaline strippable water borne rust preventive compound consisting of wax modified acrylic compounds. 2. APPLICATION This specification was released originally for material used to
3、 provide protection to the inside surfaces of bumpers made of chrome plated steel or bare, chrome plated and anodized aluminum materials. The materials dry to a soft, homogeneous film. 3. REQUIREMENTS 3.0 STANDARD REQUIREMENTS FOR PRODUCTION MATERIALS Material suppliers and part producers must confo
4、rm to the Companys Standard Requirements For Production Materials (WSS-M99P1111-A). 3.4 PHYSICAL PROPERTIES 3.4.1 Non-volatiles, min 32% (FLTM BI 102-01) 3.4.2 Color Smoke 3.4.3 Flash Point, min 93 C (ASTM D 93) 3.4.4 Shelf Stability, min 6 months The material shall be stored at ambient room tempera
5、ture below 38 C away from all sources of heat. DO NOT FREEZE. 3.4.5 Weight per Volume 1.04 +/- 0.03 kg/L (ASTM D 1475) 3.4.6 Viscosity (ASTM D 2196, Method B, use #5 spindle) 20 RPM 6000 +/- 1500 mPa.s 100 RPM 2000 +/- 500 mPa.s ENGINEERING MATERIAL SPECIFICATION WSB-M7C90-A Copyright 2015, Ford Glo
6、bal Technologies, LLC Page 2 of 3 3.5 PREPARATION OF TEST PANELS (ASTM D 609, Method A) 3.5.1 Substrate In addition to the substrates in ASTM D 609, bumper sections will be prepared and dried per 3.6.2 and evaluated per para 3.7. 3.5.2 Application Procedure Spray the test compound to a dry film thic
7、kness of 45 to 55 micrometres using an airless spray pump equipped with appropriate size orifice to produce a “flat“ (in one plane) spray pattern. 3.6 DRY FILM PROPERTIES 3.6.1 Application Temperature 20 - 30 C 3.6.2 Drying Time Material must be tack free (no transfer of material to the fingertip af
8、ter application of light pressure) after 30 minutes at 23 +/- 2 C. 3.6.3 Dry Film Thickness, min 45 micrometres (ASTM D 1212) 3.6.4 Crack Resistance (FLTM BJ 128-03) No cracks, voids or shrinkage are to be evident. 3.7 RESISTANCE PROPERTIES 3.7.1 Salt Spray Resistance, min 500 h (ASTM B 117) 3.7.2 R
9、esistance to UV Exposure, min 144 h (ASTM G 53) No mud cracking or other surface failure. 3.7.2.1 Salt Spray Resistance After 336 h Exposure, min (ASTM B 117) Expose 3.7.2 panel to salt spray per ASTM B 117. No mud cracking or other surface failure. ENGINEERING MATERIAL SPECIFICATION WSB-M7C90-A Cop
10、yright 2015, Ford Global Technologies, LLC Page 3 of 3 3.7.3 Detergent Wash Resistance (FLTM BV 116-02, modified) 3.7.3.1 Apparatus and Materials Required Detergent: Select a detergent used commercially, that has a pH range of 7.0 to 7.5 when diluted to normal use concentration. Dupont # 7 Car Wash
11、Concentrate Borden Chemicals Columbus, Ohio or equivalent 3.7.3.2 Para A, line 3 of FLTM BV 116-02 shall read: 50 +/- 2 C. 3.7.3.3 Para A, line 4 of FLTM BV 116-02 shall read: 24 hours, min. 3.7.3.4 Para B, line 1 of FLTM BV 116-02 shall read: 30 seconds duration. 3.7.4 Corrosion Resistance, min 40
12、cycles (FLTM BI 123-01) There shall be no more than 1% of the surface covered with corrosion and not more than 4.8 mm of corrosion creep-in from the edges. No perforations or deep pitting permitted. 3.7.5 Freeze-Thaw Resistance, min 3 cycles Place test panels into a freezer set at - 30 +/- 2 C for o
13、ne hour. Remove the panels and store at room temperature for one hour. Examine panels. This completes the cycle. The material must not crack, peel or lift from the surface of the test panel. 3.7.6 Heat Resistance, 121 C, min 1 h (FLTM BV 118-01, modified, material applied per para 3.5.2) Any evidenc
14、e of flow shall constitute a failure. 3.7.7 Chip Resistance at 0 C 3 C or better (ASTM D 3170) Panels coated per para 3.5, conditioned per para 3.3 of this specification, then conditioned per para 4.4 of ASTM D 3170; shall not exceed a chip rating of 3 C. 3.7.8 Stress Cracking Resistance No cracking or (FLTM BO 127-03) crazing 3.7.8.1 Para 3 - evaluate 1% strain 3.7.8.2 Para 6 - 24 hour soak with coating at 23 +/- 2 C and at 58 +/- 2 C.
